本文探討板金件折彎過程中之容差累積。以區塊累加法則推演板金件折彎後端點位置時，在某些角度組合會明顯高估導出尺寸的容差區域。本研究利用幾何圖形，詳細分析後歸納彙整。以有系統的方式表列折彎機制與容差高估的關鍵構型。建議以補正之區塊法公式推算板金元件經二次折彎後各端點之容差區域。而後研究工作另將端點位置書寫為非線性之尺度鏈結。嘗試經由線性化的變異關係式以統計法進行容差累積之估算。除此之外，研究以蒙地卡羅方法透過電腦模擬導出尺寸的變異數與分佈範圍藉以驗證容差累積分析之正確性。研究最後考量板金折彎的替代製程，分別應用補正區塊法、線性分析最差法與統計法及蒙地卡羅模擬法推演導出尺寸的容差區域。

This thesis discusses the tolerance accumulation of sheet metal products. When the tolerance zone stacking method is applied to sheet metals, the position tolerances of a free end may be overestimated in some configurations. Based on graphical illustrations, this study analyzes the locations of component tolerance zones and summarizes the tolerance zone overlapping mechanism. Then, a modified tolerance zone stacking method is proposed to evaluate the tolerance accumulation of sheet metals. Next, the position of the free end of a sheet metal is written as linearized dimension chains of process working dimensions. The variance of a resultant dimension can be calculated by the standard deviations of individual dimensions through the statistical method. The results are compared with the computer simulations using Monte Carlo method. In addition, the research studies the tolerance accumulation of other alternative bending processes for sheet metal products. The modified tolerance zone stacking method, the worst case method, and the statistical method are used to estimate the possible tolerance zones and the results are compare with the computer simulations.

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